Many people tweeted birthday wishes to the First Lady, including husband Donald Trump and step-daughter Ivanka.

Today on her birthday, she visited the National Gallery of Art's newly refurbished East Building with second Lady Kate Pence and other members of her husband and US president Donald Trump's administration.

Melania addressed the luncheon, which was not open to media, as well as welcoming photo opportunities with guests. According to a source, Melania said there was to be no birthday celebration sweets at the luncheon.

However, the Trumps are said to be planning a private celebration in the White House this evening to celebrate the milestone.